Metering device and method



March 6, 1962 R. 1.; HAYDEN ET AL 3,023,729

METERING DEVICE AND METHOD INVENTORS Q m efd wope ATTORNEYS Filed Feb.14, 1958 United States Patent 3,023,729 METERING DEVICE AND METHOD RalphL. Hayden, Vienna, and Ralph R. Steele, Parkersburg, W. Va., assignors,by mesne assignments, to

Johns-Manville Fiber Glass Inc., Cleveland, Ohio, a

corporation of Delaware Filed Feb. 14, 1958, Ser. No. 715,229 2 Claims.(Cl. 118234) The present invention relates broadly to the treatment ofcontinuous strands of textile materials and more particularly to amethod and apparatus especially adapted for applying predeterminedamounts of liquid sizes, binder or lubricants to textile strands.

This invention is of particular utility and will be described hereinwith reference to the coating of strands of glass fibers produced bygrouping endless filaments of glass that are drawn and attenuated toextremely fine diameters. However, it is to be understood that theinvention may also be used in connection with other processes and, ingeneral, is adapted for use wherever filaments, natural or synthetic,are grouped and coated to form substantially continuous strands.

In forming continuous strands from finely drawn glass filaments, wherethe filaments are grouped into strand form by passing said filamentsover a guide, the common practice is to provide the guide withapplicator means for supplying a liquid coating material, such as alubricant, size or binder, to said filaments. The liquid lubricant,binder or size serves to prevent the filaments within the strand fromscratching each other, or the coating may serve to give mass integrityto the group of filaments in strand form, thereby preventing loose endsfrom fraying or breaking apart from the strand.

it is customary in coating strands by the aforementioned method toprovide the guide with a pad of felt or other absorbent material. Thepad is then saturated with the liquid coating material and serves towipe the coating liquid onto the filaments as they pass thereover. Theliquid is usually applied to the absorbent pad by means of a flexibletube positioned directly over said pad and connected directly to aliquid supply line.

Ordinarily, in the above-described system, where the liquid is allowedto flow from a tube suspended above the applicator pad onto said pad, avalve is provided in circuit with the flexible tube in order that anoperator may adjust the flow so that the pad is kept completelysaturated with the liquid coating material thereby assuring a properwiping action of the filaments passing thereover.

It has been found however that, in actual practice, the operator seldommakes the proper adjustment for providing an optimum flow of liquidcoating material onto the applicator pad. Thus an operator sometimes mayclose the valve to too great an extent, and this in turn results in anincomplete saturation of the pad and improper coating of the strand. Themore usual failing is that the operator will open the valve to too greatan extent, which of course insures saturation of the applicator pad but,in turn, results in flooding the pad with the liquid coating material.The latter case, although resulting in a proper coating of the strand,results in an excessiveloss of coating material, which results inexcessive production costs in the over-all commercial operation.

The present invention aims to overcome the afore mentioned dificultiesby providing a novel method and apparatus whereby predeterminedquantities of liquid coating materials may be metered onto theapplicator pad.

It is another object of this invention to provide a novel meteringdevice which permits the application of predetermined amounts of liquidcoating material at an optimum and uniform flow and which, at the sametime, does not require periodic valve adjustments in the liquid supplyline.

Other objects and advantages of the invention will become apparent fromthe following description taken in conjuncton with the drawings.

In the drawings, wherein like numerals are employed to designate likeparts throughout the same:

FIG. 1 is an elevational view of the apparatus of this invention shownin conjunction with two filament forming and drawing devices in series;

FIG. 2 is an enlarged sectional view of the metering deevice of thisinvention taken along the line 22 of FIG. 1;

FIG. 3 is an enlarged sectional view taken along the line 3-3 of FIG. 2;

FIG. 4 is a side view of FIG. 2; and

FIG. 5 is a side view of the sealing member.

Referring now to the drawings, and particularly to FIG. 1, the letter Adesignates generally a filament forming and drawing apparatus formechanically drawing and attenuating molten glass in the form ofcontinuous fine glass fibers or filaments. This apparatus comprises acontainer or bushing 10 for molten glass. The molten glass flows fromthe container through a plurality of small orifices in the bottomthereof in the form of individual streams of molten glass and thesestreams of molten glass are drawn downwardly and attenuated into fineglass fibers or filaments 11 by means of a winding spindle 12 on whichthe fibers are wound to form a package with the aid of a suitabletraverser 13, as is well known in the art.

Located intermediate the bushing 10 and winding spindle 12 is a guide,indicated generally by the numeral 14, adapted to group and combine thefilaments 11 into a strand 15 and to apply a suitable size, binder orother liquid coating material to the filaments substantially at thepoint at which they are grouped. The guide 14 ordinarily comprises anarm or plate 16 provided with an applicator pad 17 of felt or othersuitable absorbent material for receiving the coating liquid as it flowsfrom the flexible tube 18 and for wiping said liquid coating materialonto the filaments as they are drawn thereover.

The liquid supply apparatus which is designed to provide for apredetermined optimum and uniform flow of liquid coating material ontothe applicator pad is indicated generally by the numeral 19. Thisapparatus comprises a reservoir 20 for storing the liquid coatingmaterial and a conduit 21 through which the liquid is forced from thecontainer under a constant pressure by means of a pump 22 interposed inthe conduit 21. Carried by the conduit, at a point above the applicatorpad 17, is a metering device, indicated generally by the numeral 23, andleading directly from this metering device to a position directly overthe applicator pad 17 is the flexible tube 18 for supplying a constantflow of liquid coating material to said applicator pad.

The metering device 23 comprises a housing 24, a readily compressiblesealing member 25 located in said housing, a backing plate 26 secured tothe housing, and a needle or capillary tube 27, extending through thesealing member. The housing 24 is shown as being in the form of arectangular block having a circular hole 28 drilled therethrough, andbeing secured to the conduit 21 by suitable means such as by welding orthe like. Circular holes 29 and 30 are provided, respectively, in theconduit 21 and backing plate 26. The holes 29 and 30 are in alignmentwith one another and are relatively smaller than the hole 28 in thehousing, being disposed centrally thereof.

The sealing member 25 is preferably formed of rubber and comprises abody portion 31 having two oppositely directed nipple-like protuberances32 and 33. The body portion 31 is received within the opening 25 inhousing 24, with the protuberance 32 projecting through the hole 30 inbacking plate 26 and the protuberance 33 projecting through the hole 29in the conduit 21. A hole 34 is drilled centrally through the bodyportion 31 and nipple-like protuberance 32, as shown by the dotted lines34 in FIG. 5,

while protuberance 33 is slit to form the two opposing lips 35 and 36.

In practice, the tube 27 is inserted through the hole 34 in the sealingmember 25 so that the opposite ends of the tube project beyond thesealing member as shown in FIG. 3. The sealing member 25, carrying tube27, is then positioned in the housing 24 so that the nipple-like portion33 extends through hole 29 in conduit 21. The backing plate 26 is thensuitably secured over the body 31 of the sealing member 25 and to theoutwardly directed wall of the housing 24 such as by means of screws 37.The parts 31, 32 and 33 of sealing member 25 are all slightly largerthan the respective holes in which they are positioned so as to providea liquid tight sealbetween tube 27 and the housing 24, backing plate 26and conduit 21 respectively.

It will be readily evident that the sealing member could be completelydrilled therethrough to receive the tube 27. However, it has been found,in actual practice, that a more perfect seal results between the wallsof hole 29 and tube 27 if the nipple-like member 33 is slit as shown inFIG. to provide the opposing lips 35 and 36 which serve to grip the tube27. Finally, one end of the tube 18 is fitted over the outwardlyprojecting end of tube 27, with its opposite end in position over theapplicator pad 17.

In operation, the liquid coating material in tank 20 is pumped throughconduit 21 by means of pump 22 which maintains a constant pressure onthe liquid in conduit 21. This liquid then flows under constant pressurethrough the metering device 23, by means of the needle or capillary tube27, into and through the flexible tube 18 onto the applicator pad 17.The amount of liquid flowing through the tube 18 will be proportional tothe size of the opening in, and the length of, the needle or capillarytube 27 and the pressure and viscosity of the liquid coating material inconduit 21. Once the optimum amount of liquid flow necessary forcomplete saturation of the applicator pad has been ascertained, the sizeand length of the capillary tube and the fluid pressure necessary forachieving this flow may be readily determined.

By way of example, it was determined that a flow of 76 cc. of liquidbinder per minute would be the optimum flow required to saturate theapplicator pad. The liquid binder in the supply conduit was under poundspressure and the length of the delivery tube, extending from themetering device to the applicator pad, was 72 inches. The tube 27 in themetering device which would deliver the required flow was 1 /2 inches inlength and had a 0.018 inch orifice.

It is also within the scope of this invention to encompass liquid supplysystems diifering from that shown in FIG. 1. Thus, conduit 21 may becontinued so as to connect into the reservoir 20, thereby forming acomplete cycle. Also, a gravity feed of liquid coating material may beestablished by positioning the liquid reservoir above the meteringdevice. The critical factor which must be maintained constant is thepressure of the liquid coating material entering the tubular portion ofthe metering device and other well-known apparatus which will accomplishthis result are within the scope of this invention.

Also, as shown in FIG. 1, the metering apparatus of this invention maybe employed to serve one or more additional filament forming and drawingdevices B the only limitation being the elfective pressure which must bestituted for the guide 14,

As shown in the drawings, the needle or capillary tube 27 enters conduit21 from the side. This arrangement is preferable as it places the entryorifice of the tube at a point well above the bottom of conduit 21,which may possibly contain sediment to a certain extent. It iscontemplated, however, that the needle or capillary tube may bepositioned in various parts of the conduit 21 and yet be within thescope of the invention.

It is to be understood that the form of the invention herewith shown anddescribed is to be taken as the preferred embodiment of the same, andthat various changes in the shape, size and arrangement of parts may beresorted to without departing from the scope of the subjoined claims.

We claim:

1. An apparatus for supplying a predetermined and constant volume ofliquid coating material to a plurality of glass fiber strands comprisinga supply of coating material, a conduit connected to the liquid supply,pressurizing means to convey liquid coating from the supply through saidconduit at a constant pressure, an applicator of liquid coating, acapillary tube, of constant internal cross-sectional area and being of apredetermined length, projecting into the passing stream within saidconduit and being approximately at right angles to the direction of flowof the coating material so as to permit said coating material to exit ata predetermined rate as determined by the capillary characteristics ofthe tube, the pressure head on the coating material and the viscositythereof, said tube projecting stant volume of liquid coating material toa plurality of glass fiber strands comprising a supply of coatingmaterial, a conduit connected to the liquid supply, pressurized means toconvey liquid coating from the supply through said conduit at a constantpressure, an applicator of liquid coating, a capillary tube projectinginto the passing stream within said conduit and being approximately atright angles to the direction of flow of the coating material so as topermit said coating material to exit at a predetermined rate asdetermined by the capillary characteristics of the tube, the pressurehead on the coating material, and the viscosity thereof, a housingsecured to said conduit encompassing the tube adjacent the conduit, adeformable sealing member within said housing and through which the tubepasses, a portion of said sealing member comprising spaced lipsprojecting into the conduit, said lips being tightly engaged with saidtube and the conduit wall to prevent leakage out of the conduit adjacentthe tube, means to conduct coating material from the tube to theapplicator, and means to combine a plurality of glass fiber strands intoa single strand adjacent the applicator and to bring said glass fiberstrands into contact with the coating material on the applicator.

References Citedin the file of this patent UNITED STATES PATENTS1,208,664 Russak et al Dec. 12, 1916 1,449,342 Morrell Mar. 20, 19231,621,303 Altemus Mar. 15, 1927 1,934,796 Friederich Nov. 14, 19332,224,149 Fisher Dec. 10, 1940 2,373,078 Kleist Apr. 3, 1945 2,659,343Kucher Nov. 17, 1953 2,693,096 Quinn Nov. 2, 1954

